Pinwheel Galaxy M101

Object Information:

The Pinwheel Galaxy (also known as Messier 101M101 or NGC 5457) is a face-on spiral galaxy distanced 21 million light-years (six megaparsecs)[3] away in the constellation Ursa Major, first discovered by Pierre Méchainon March 27, 1781, and communicated to Charles Messier who verified its position for inclusion in the Messier Catalogue as one of its final entries.

On February 28, 2006, NASA and the ESA released a very detailed image of the Pinwheel Galaxy, which was the largest and most detailed image of a galaxy by Hubble Space Telescope at the time.[8] The image was composed from 51 individual exposures, plus some extra ground-based photos.

On August 24, 2011, a Type Ia supernovaSN 2011fe, was discovered in M101.

Image date:

March 11, 2016

Exposure Information:

1h 5 minutes exposure

Lights: 13x300" 800ISO
Darks: 6
Flats: 30
Bias: 50

Temperature 9ºC

Moon phase 12%

Note: after several attempts the guiding system failed, so I started imaging unguided, allowing me to take subs at maximum of 300 seconds. I had to discard most of the 30 planned images. Finally, i selected the "best" 13 images (or the least worse).

Imaged at:
Prades, Tarragona, CATALUNYA - SPAIN

Optics - GSO- 200/1000 Newtonian f/5
Camera - Canon 450D moded (IR filter removed)
Mount - Sky-Watcher Neq6 PROII